1 files changed, 46 insertions, 58 deletions

diff --git a/clang/lib/Sema/SemaStmtAttr.cpp b/clang/lib/Sema/SemaStmtAttr.cpp
index 595aa3656eb..4cb0fde11d0 100644
--- a/clang/lib/Sema/SemaStmtAttr.cpp
+++ b/clang/lib/Sema/SemaStmtAttr.cpp
@@ -47,13 +47,11 @@ static Attr *handleLoopHintAttr(Sema &S, Stmt *St, const AttributeList &A,
                                 SourceRange) {
   IdentifierLoc *PragmaNameLoc = A.getArgAsIdent(0);
   IdentifierLoc *OptionLoc = A.getArgAsIdent(1);
-  IdentifierInfo *OptionInfo = OptionLoc->Ident;
-  IdentifierLoc *ValueLoc = A.getArgAsIdent(2);
-  IdentifierInfo *ValueInfo = ValueLoc ? ValueLoc->Ident : nullptr;
+  IdentifierLoc *StateLoc = A.getArgAsIdent(2);
   Expr *ValueExpr = A.getArgAsExpr(3);
 
-  assert(OptionInfo && "Attribute must have valid option info.");
-
+  bool PragmaUnroll = PragmaNameLoc->Ident->getName() == "unroll";
+  bool PragmaNoUnroll = PragmaNameLoc->Ident->getName() == "nounroll";
   if (St->getStmtClass() != Stmt::DoStmtClass &&
       St->getStmtClass() != Stmt::ForStmtClass &&
       St->getStmtClass() != Stmt::CXXForRangeStmtClass &&
@@ -69,13 +67,16 @@ static Attr *handleLoopHintAttr(Sema &S, Stmt *St, const AttributeList &A,
 
   LoopHintAttr::OptionType Option;
   LoopHintAttr::Spelling Spelling;
-  if (PragmaNameLoc->Ident->getName() == "unroll") {
-    Option = ValueLoc ? LoopHintAttr::UnrollCount : LoopHintAttr::Unroll;
+  if (PragmaUnroll) {
+    Option = ValueExpr ? LoopHintAttr::UnrollCount : LoopHintAttr::Unroll;
     Spelling = LoopHintAttr::Pragma_unroll;
-  } else if (PragmaNameLoc->Ident->getName() == "nounroll") {
+  } else if (PragmaNoUnroll) {
     Option = LoopHintAttr::Unroll;
     Spelling = LoopHintAttr::Pragma_nounroll;
   } else {
+    assert(OptionLoc && OptionLoc->Ident &&
+           "Attribute must have valid option info.");
+    IdentifierInfo *OptionInfo = OptionLoc->Ident;
     Option = llvm::StringSwitch<LoopHintAttr::OptionType>(OptionInfo->getName())
                  .Case("vectorize", LoopHintAttr::Vectorize)
                  .Case("vectorize_width", LoopHintAttr::VectorizeWidth)
@@ -87,35 +88,10 @@ static Attr *handleLoopHintAttr(Sema &S, Stmt *St, const AttributeList &A,
     Spelling = LoopHintAttr::Pragma_clang_loop;
   }
 
-  int ValueInt = -1;
-  if (Option == LoopHintAttr::Unroll &&
-      Spelling == LoopHintAttr::Pragma_unroll) {
-    if (ValueInfo)
-      ValueInt = (ValueInfo->isStr("disable") ? 0 : 1);
-  } else if (Option == LoopHintAttr::Unroll &&
-             Spelling == LoopHintAttr::Pragma_nounroll) {
-    ValueInt = 0;
-  } else if (Option == LoopHintAttr::Vectorize ||
-             Option == LoopHintAttr::Interleave ||
-             Option == LoopHintAttr::Unroll) {
-    // Unrolling uses the keyword "full" rather than "enable" to indicate full
-    // unrolling.
-    const char *TrueKeyword =
-        Option == LoopHintAttr::Unroll ? "full" : "enable";
-    if (!ValueInfo) {
-      S.Diag(ValueLoc->Loc, diag::err_pragma_loop_invalid_keyword)
-          << TrueKeyword;
-      return nullptr;
-    }
-    if (ValueInfo->isStr("disable"))
-      ValueInt = 0;
-    else if (ValueInfo->getName() == TrueKeyword)
-      ValueInt = 1;
-    else {
-      S.Diag(ValueLoc->Loc, diag::err_pragma_loop_invalid_keyword)
-          << TrueKeyword;
-      return nullptr;
-    }
+  int ValueInt = 1;
+  LoopHintAttr::LoopHintState State = LoopHintAttr::Default;
+  if (PragmaNoUnroll) {
+    State = LoopHintAttr::Disable;
   } else if (Option == LoopHintAttr::VectorizeWidth ||
              Option == LoopHintAttr::InterleaveCount ||
              Option == LoopHintAttr::UnrollCount) {
@@ -124,28 +100,39 @@ static Attr *handleLoopHintAttr(Sema &S, Stmt *St, const AttributeList &A,
     llvm::APSInt ValueAPS;
     if (!ValueExpr || !ValueExpr->isIntegerConstantExpr(ValueAPS, S.Context) ||
         (ValueInt = ValueAPS.getSExtValue()) < 1) {
-      S.Diag(ValueLoc->Loc, diag::err_pragma_loop_invalid_value);
+      S.Diag(A.getLoc(), diag::err_pragma_loop_invalid_value);
       return nullptr;
     }
-  } else
-    llvm_unreachable("Unknown loop hint option");
+  } else if (Option == LoopHintAttr::Vectorize ||
+             Option == LoopHintAttr::Interleave ||
+             Option == LoopHintAttr::Unroll) {
+    // Default state is assumed if StateLoc is not specified, such as with
+    // '#pragma unroll'.
+    if (StateLoc && StateLoc->Ident) {
+      if (StateLoc->Ident->isStr("disable"))
+        State = LoopHintAttr::Disable;
+      else
+        State = LoopHintAttr::Enable;
+    }
+  }
 
-  return LoopHintAttr::CreateImplicit(S.Context, Spelling, Option, ValueInt,
-                                      A.getRange());
+  return LoopHintAttr::CreateImplicit(S.Context, Spelling, Option, State,
+                                      ValueInt, A.getRange());
 }
 
-static void CheckForIncompatibleAttributes(
-    Sema &S, const SmallVectorImpl<const Attr *> &Attrs) {
-  // There are 3 categories of loop hints attributes: vectorize, interleave, and
-  // unroll. Each comes in two variants: a boolean form and a numeric form.  The
-  // boolean hints selectively enables/disables the transformation for the loop
-  // (for unroll, a nonzero value indicates full unrolling rather than enabling
-  // the transformation).  The numeric hint provides an integer hint (for
-  // example, unroll count) to the transformer. The following array accumulates
-  // the hints encountered while iterating through the attributes to check for
-  // compatibility.
+static void
+CheckForIncompatibleAttributes(Sema &S,
+                               const SmallVectorImpl<const Attr *> &Attrs) {
+  // There are 3 categories of loop hints attributes: vectorize, interleave,
+  // and unroll. Each comes in two variants: a state form and a numeric form.
+  // The state form selectively defaults/enables/disables the transformation
+  // for the loop (for unroll, default indicates full unrolling rather than
+  // enabling the transformation).  The numeric form form provides an integer
+  // hint (for example, unroll count) to the transformer. The following array
+  // accumulates the hints encountered while iterating through the attributes
+  // to check for compatibility.
   struct {
-    const LoopHintAttr *EnableAttr;
+    const LoopHintAttr *StateAttr;
     const LoopHintAttr *NumericAttr;
   } HintAttrs[] = {{nullptr, nullptr}, {nullptr, nullptr}, {nullptr, nullptr}};
 
@@ -179,8 +166,8 @@ static void CheckForIncompatibleAttributes(
     if (Option == LoopHintAttr::Vectorize ||
         Option == LoopHintAttr::Interleave || Option == LoopHintAttr::Unroll) {
       // Enable|disable hint.  For example, vectorize(enable).
-      PrevAttr = CategoryState.EnableAttr;
-      CategoryState.EnableAttr = LH;
+      PrevAttr = CategoryState.StateAttr;
+      CategoryState.StateAttr = LH;
     } else {
       // Numeric hint.  For example, vectorize_width(8).
       PrevAttr = CategoryState.NumericAttr;
@@ -195,14 +182,15 @@ static void CheckForIncompatibleAttributes(
           << /*Duplicate=*/true << PrevAttr->getDiagnosticName(Policy)
           << LH->getDiagnosticName(Policy);
 
-    if (CategoryState.EnableAttr && CategoryState.NumericAttr &&
-        (Category == Unroll || !CategoryState.EnableAttr->getValue())) {
+    if (CategoryState.StateAttr && CategoryState.NumericAttr &&
+        (Category == Unroll ||
+         CategoryState.StateAttr->getState() == LoopHintAttr::Disable)) {
       // Disable hints are not compatible with numeric hints of the same
       // category.  As a special case, numeric unroll hints are also not
       // compatible with "enable" form of the unroll pragma, unroll(full).
       S.Diag(OptionLoc, diag::err_pragma_loop_compatibility)
           << /*Duplicate=*/false
-          << CategoryState.EnableAttr->getDiagnosticName(Policy)
+          << CategoryState.StateAttr->getDiagnosticName(Policy)
           << CategoryState.NumericAttr->getDiagnosticName(Policy);
     }
   }